CA2072170A1 - Solid-solid separations utilizing alkanol amines - Google Patents
Solid-solid separations utilizing alkanol aminesInfo
- Publication number
- CA2072170A1 CA2072170A1 CA002072170A CA2072170A CA2072170A1 CA 2072170 A1 CA2072170 A1 CA 2072170A1 CA 002072170 A CA002072170 A CA 002072170A CA 2072170 A CA2072170 A CA 2072170A CA 2072170 A1 CA2072170 A1 CA 2072170A1
- Authority
- CA
- Canada
- Prior art keywords
- solid
- silica
- separation
- alkanol amine
- weight percent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000000926 separation method Methods 0.000 title claims abstract description 26
- 150000001412 amines Chemical class 0.000 title claims abstract description 24
- 239000007787 solid Substances 0.000 title claims description 39
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 45
- 239000002002 slurry Substances 0.000 claims abstract description 25
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 21
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 6
- 239000011707 mineral Substances 0.000 claims abstract description 6
- 238000000034 method Methods 0.000 claims description 22
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 claims description 12
- HZAXFHJVJLSVMW-UHFFFAOYSA-N 2-Aminoethan-1-ol Chemical compound NCCO HZAXFHJVJLSVMW-UHFFFAOYSA-N 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 2
- 239000012736 aqueous medium Substances 0.000 claims description 2
- 229910052739 hydrogen Inorganic materials 0.000 claims description 2
- 239000001257 hydrogen Substances 0.000 claims description 2
- 125000002768 hydroxyalkyl group Chemical group 0.000 claims description 2
- 230000003993 interaction Effects 0.000 claims description 2
- JTJMJGYZQZDUJJ-UHFFFAOYSA-N phencyclidine Chemical class C1CCCCN1C1(C=2C=CC=CC=2)CCCCC1 JTJMJGYZQZDUJJ-UHFFFAOYSA-N 0.000 abstract description 3
- 238000005516 engineering process Methods 0.000 abstract description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 21
- 229910052742 iron Inorganic materials 0.000 description 10
- 239000002245 particle Substances 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000012141 concentrate Substances 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 229910052681 coesite Inorganic materials 0.000 description 4
- 229910052906 cristobalite Inorganic materials 0.000 description 4
- SZVJSHCCFOBDDC-UHFFFAOYSA-N iron(II,III) oxide Inorganic materials O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 4
- 239000006148 magnetic separator Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 238000005070 sampling Methods 0.000 description 4
- 235000012239 silicon dioxide Nutrition 0.000 description 4
- 229910052682 stishovite Inorganic materials 0.000 description 4
- 229910052905 tridymite Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 229910052595 hematite Inorganic materials 0.000 description 3
- 239000011019 hematite Substances 0.000 description 3
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 3
- 230000035699 permeability Effects 0.000 description 3
- 239000008247 solid mixture Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 description 3
- HXKKHQJGJAFBHI-UHFFFAOYSA-N 1-aminopropan-2-ol Chemical compound CC(O)CN HXKKHQJGJAFBHI-UHFFFAOYSA-N 0.000 description 2
- 229910019142 PO4 Inorganic materials 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 2
- 238000013019 agitation Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 229940102253 isopropanolamine Drugs 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 2
- 239000010452 phosphate Substances 0.000 description 2
- 238000012216 screening Methods 0.000 description 2
- 238000011282 treatment Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005188 flotation Methods 0.000 description 1
- 238000009291 froth flotation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000010297 mechanical methods and process Methods 0.000 description 1
- 235000020030 perry Nutrition 0.000 description 1
- 238000002203 pretreatment Methods 0.000 description 1
- 230000009290 primary effect Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 238000001238 wet grinding Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
- B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
- B03B1/00—Conditioning for facilitating separation by altering physical properties of the matter to be treated
- B03B1/04—Conditioning for facilitating separation by altering physical properties of the matter to be treated by additives
Landscapes
- Manufacture And Refinement Of Metals (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Paper (AREA)
Abstract
ABSTRACT
The separation of silica or siliceous gangue from one or more desired minerals in an aqueous slurry via mechanic mean is improved by the addition of a small amount of an alkanol amine to the slurry.
Examples of separation techniques benefiting from this technology include cyclones, tables and spiral separators.
38,597-F
The separation of silica or siliceous gangue from one or more desired minerals in an aqueous slurry via mechanic mean is improved by the addition of a small amount of an alkanol amine to the slurry.
Examples of separation techniques benefiting from this technology include cyclones, tables and spiral separators.
38,597-F
Description
SOLID-SOLID SEPARATIONS
UTILIZING ALKANOL AMINES
This invention relates to the selective separation of certain solids from solid mixtures containing silica or qiliceous gangue.
The processing of mixed solids in particulate form i~ widely practiced in industry. The solids are usually ~eparated into individual components (solid/solid separation) by a variety of engineering processes using inherent differences between the various solid components. These inherent differences include color, size, conductivity, reflectance, density, magnetic permeability, electrical conductivity and surface wettability. This latter characteristic, surface wettability, is exploited in froth flotation, flooculation and agglomeration processes whiah rely heavily on various chemical treatments to enhance separation.
Differences in the other characteristic~
identified above, especially size, conductivity, den~ity, magnetic permeability and electrical conductivity, have typically been utilized to obtain separation via various mechanical method~. These 38,597-F -1-, .
. . .
.
UTILIZING ALKANOL AMINES
This invention relates to the selective separation of certain solids from solid mixtures containing silica or qiliceous gangue.
The processing of mixed solids in particulate form i~ widely practiced in industry. The solids are usually ~eparated into individual components (solid/solid separation) by a variety of engineering processes using inherent differences between the various solid components. These inherent differences include color, size, conductivity, reflectance, density, magnetic permeability, electrical conductivity and surface wettability. This latter characteristic, surface wettability, is exploited in froth flotation, flooculation and agglomeration processes whiah rely heavily on various chemical treatments to enhance separation.
Differences in the other characteristic~
identified above, especially size, conductivity, den~ity, magnetic permeability and electrical conductivity, have typically been utilized to obtain separation via various mechanical method~. These 38,597-F -1-, .
. . .
.
2 207217~
methods include the use of screening, wet cyclones, hydroseparators, centrifuges, heavy media devices, desliming vessels, jigs, wet tables, spirals, magnetic separators and electro~tatic separators. The proper use of water is recognized as critical to the efficiency of such methods. A fundamental driving force in most of these operations ls the control of how particles flow, settle or are magnetically or electrically manipulated in an aqueous environment. Factors such as the density (percent solids by weight) of the solid mixture solutions in water; the degree of mechanical agitation of such pulps; the size of particles in the solid mixtures; and the equipment design and size all act and/or are controlled in a complex fashion to optimize the appropriate solid separation in any specific operation. While some universal scientific and engineering concepts can be applied in such separations, the complexity of such operations frequently requires empirical testing and adjustment to effect a suitable separation.
The present invention is a solid/solid separation process wherein an aqueous slurry of solids containing silica or siliceous gangue and one or more desired minerals is mechanically separated, characterized by the addition of an amount of an alkanol amine to the aqueous slurry effective to modify the interaction of the silica or siliceous gangue with the aqueous medium such that separation of the silica or siliceous gangue from the remainder of the solid minerals is enhanced when compared to processes conducted in the absence of the alkanol amine.
38,597-F -2-;
;,, -3- ~
Mechanical separation refers to those methods in which an aqueous slurry of solid particles is separated based on the physical characteristics of the particles. Such physical characteristics include size, conductivity, density, magnetic permeability and electrical conductivity.
Typical means used to separate solid/solid pulps include jigs, wet tables, spirals, heavy media devices, screening, wet cyclones, hydroseparators, centrifuges, desliming vessels, magnetic separators and electrostatic separators. These techniques are well known in the art and are extensively practiced. A
general discussion of these techniques is found in Perry's Chemical Engineers' Handbook, Sixth Edition, edited by Don W. Green, McGraw-Hill Book Company.
The t~pical manner of practicing these method~
of mechanical separation is not modified by the practice of this invention, other than by the addition of the alkanol amine.
Typically, mechanical separation is used to separate particulate solids with sizes ranging from about 100 millimeters (mm) in diameter down to particles of less than 0.001 mm in diameter. Particles of this size range may be obtained in various ways, but are typically obtained by wet grinding. Once ground, the particles are present in an aqueous slurry ranging from 2 to 70 percent by weight solids depending on various factors such a~ the particular method of solid separation used and other related operating condition 38,597-F -3-, , ~ .
`2072i~1~
The alkanol amines of the present invention preferably correspond to the formula Wherein R1, R2 and R3 are individually in each occurrence hydrogen or a C(1-6) hydroxy alkyl moiety.
Preferred alkanol amines are monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, hexanolamine and mixtures thereof. The most preferred alkanolamine is diethanolamine. It will be recognized by those skilled in the art that commercial methods of production of such compound~ as diethanolamine result in a product containing some by-products such as other alkanol amines. Such commercial products are operable in the practice of the present invention. It will also be recognized that the alkanol amines are themselves compounds and do not form a part of a larger molecule.
The amount of such alkanol amines used in the process of this invention is that which is effective to result in increased recovery of the desired solid either through improved grade, improved recovery or a combination thereof. This amount typically ranges from 0.01 to 10 kilogram of alkanol amine per metric ton of dry feed. Preferably, the amount ranges from 0.05 to 1 kg per metric ton and more preferably from 0.1 to 0.5 kg per metric ton.
The alkanol amine is added to the aqueous ; slurry feed prior to the feed being fed to the separation device. It is preferred that, when the ~olid feed is subjected to grinding that the alkanol amine be added to the grinding step.
:,, 38,597-F -4-, .. . .
Example 1 -- Ma~netic SeParation A continuous 12 inch diameter by 7 inch width wet drum magnetic separator (ERIEZ Laboratory Model 500-11-11) is set up to run at twenty-five percent of maximum intensity using 115 volts and 5.2 amp input.
Several batches of feed material were prepared using a mixture of magnetite with a specific gravity of 3.96 and silica with a specific gravity of 2.67. The feed mixture of particles was 15.5 weight percent magnetite.
The feed mixtures were prepared in aqueous slurry form at 20 weight percent solids in a special highly agitated slurry holding tank that provided a uniform feed slurry to the magnetic separator. In one run, no pre-treatment was used and in the second run, the slurry was treated with diethanolamine in an amount equivalent to 0.45 kg per metric ton of dry feed solids. Each run wa~
operated at steady state conditions and samples were collected from the concentrate, overflow and tail for five minutes. The samples were dried, weighed and an iron analy~is done with a D.C. plasma spectrometer to determine that fate of the magnetite. The re~ults obtained are shown in Table I below.
38,597-F -5-TABLE I
_= ~ ~ i A ~ Fr G t I n 1 Or~e ~r lle~ ~ very ~f re Comparison Concentrate 0.328 0.423 0.874 Run ~ Overflow 0.034 0.006 0.001 Tail 0.638 0.031 0.125 DEA Concentrate 0.292 0.482 0.925 Run Overflow 0.035 0.001 0.000 Tail 0.673 0.017 0.075 ~Not an emb ~diment of t~ e invention The data above shows that the addition of diethanolamine results in more iron being recovered in the concentrate and less iron lost in the tailings.
ExamDle 2 A 0.6 x 1.3 m laboratory table separator was used with 0.01 m openings between the rib~ which measured 0.003 by 0.0017 m. The table angle was 10 degrees from hori~ontal with moderate agitation and water washing. The feed material used was 15.5 weight percent magnetite with the remainder silica. The same slurry feeding system was used and all table operating conditions and slurry feed rates were held constant in each run. Two steady state runs were made at 20 weight perçent solids in an aqueous slurry. Sampling of product, middlings and tail were made for seven minutes 3o in each run. All samples were dried, weighed and analyzed for iron using a D.C. plasma spectrometer. The definition of samples with this table is defined by the physical placement of overflow trays. The re3ults obtained are shown in Table II below.
38,597-F _~_ ' : l TABLE II
Grade of Fractlonal Sampling Fractional Fe in Recovery of Fe Point Wt. Split Sample ln Sample i Comparison Product 0.213 0.359 0.493 Run ~ Meddlings 0.276 0.148 0.264 Tail 0.511 0.074 0.244 , DEA Product 0.233 0.378 0.568 Run Meddlings 0.117 0.178 ` 0.134 Tail 0.650 0.071 0.298 ~Not an emb( )diment of t~ e invention The data above shows a significant increase in the amount of iron recovered. The primary effect appears to be in the ~hift of iron from the middlings to the product.
Example 3 Samples of ~pecified ores (300 g each) were ground in an eight inch diameter ball mill using one inch diameter stainlesc steel balls to obtain approximately 50 weight percent less than 37 micrometers in diameter. The mill was rotated at 60 revolutions per minute (RPM) and 600 cm3 of water was added along with any desired chemical to the mill before grinding was initiated. When the target grind size is achieved, the mill contents were transferred to a 10 liter vessel and the contents were diluted with water to make up a total pulp volume of 10 liters. The dilute pulp was mixed for one minutes at 1800 RPM and then 3ettling wa~ allowed to occur for five minutes. Then seven liters of the pulp from the upper zone of the veq~el were decanted. The dry weights of both the decanted ~olid~ and the settled solids were recorded and the weight percent in the 38,597-F -7-.
deslimed fraction was calculated. The higher this deslime weight fraction, the more efficient the desliming or fine particle removal process.
The three ores chosen were an iron ore containing 32 weight percent silica; a copper ore containing 76 weight percent silica and siliceous gangue and a phosphate ore containing 44 weight percent silica and siliceous gangue. The identity and dosage of the alkanol amines used is shown in Table III below.
3o 38,597-F -8-a = a~ cr~ ~ rr~ ~ ~ n _ ~ o ~ s . ......... ..... . . .
~ 0~ ,S" O ~ C~ ~ ~ ~ ~ 'D ~ ~O 'D
o o ~ u~ ~ o _ ~ .
.~ a) ~D ~ ~ O ~ o ,_ ~ ~
CL S ~ CO ~ N CJ` O ~1S~ `D O O O
o co a~ coc~c~ a~ CJ~ a~
'O _ _ __ s a~ ~ CJ~ ~O ~ L~ O ~ ~ N ~) s., s ~ o ~ u~ ~ ~ ~ t--CO N ~ ~I
~ ,_, 0 COcO COCOCOCOCO CO CO CO
'O ~ _ _ _ _ O .5: 0 ~ CC) ~ O ~O`D U'\ ~ ~
~ o ~ N N N N N ~ t~ N N N
o~ ~: _ _ C~
,s., _ _ _ C~ EL1 O oQ. O N O t~i ~1~ ~ CO ~ CO
~ ~ ~ -- --~ ~ a~ ~r ~u~ ~ s ~ o .~ O S., ~r) ~ ~ J D--J 'D 1~ O co 3 s O ~J ~ J ~ _ N .-~J _ _ _ ~ :
0~ I ~ 000 U- ~ O I~
o ' ~' I ' .
207217~
1 o--The data in Table III shows that various alkanol amines are effective in increasing the percentage of very fine particles removed in a desliming process. As in this example, the very fine (high surface area) particle~ present in many finely ground mineral samples are rich in undesired silica and/or siliceous gangue. Their removal is important in subsequent treatment steps involving the addition of chemical reagents such as in flotation.
Example 4 A standard five turn Humphrey spiral was set up with constant feed pulp and feed water capability. Only one concentrate port was used (remainder were sealed off with ~mooth discs) to obtain consistent steady-state condition~. Sufficient wash water was supplied to maintain a rea~onably ~mooth flow pattern over the concentrate port which was located at the bottom of the first spiral turn. Each run described in Table IV below consists of a five-minute sampling period with the feed rate being 3.0 kg of a 20 weight percent solid slurry over the five minute period. Four different ores were used: (1) cassiterite (SnO2) containing 0.65 weight percent tin with 1.2 weight percent larger than 10 mesh and 9.9 weight percent ~maller than 200 mesh; (2) coarse hematite (FeO3) containing 33.1 weight percent iron with 8.6 weight percent being larger than 10 mesh and 2.1 weight percent being smaller than 200 mesh; (3) fine hematite containing 47.4 weight percent iron with 0.0 weight percent being larger than 10 mesh and 28.3 weight percent being smaller than 200 mesh; and (4) coarse rutile (TiO2) containing 8.8 weight percent iron with 11.4 weight percent being larger than 10 mesh and 4.9 38,597-F -10-;, .
.
weight percent being smaller than 200 mesh. In each run, all samples were collected, dried and weighed and metal content determined by a D. C. plasma spectrograph When the diethanolamine was used, the feed slurry was conditioned for one minute in a stirred tank before 5 slurry feed addition to the spiral was initiated. The results obtained are shown in Table IV below.
TABLE IV
Wt % OreGrade of % of Metal Ore RecoveredRecovered Ore Recovered SnO2 No DEA DEANo DEA DEANo DEA D~A
Concentrate34.1 39.61.34 1.3270.3 80.4 Tail 65.9 60.40.29 0.2129.4 19.5 Coarse Fe20~
Concentrate38.0 35.438.1 45.043.7 48.1 Tail 62.0 64.630.1 26.556.4 51.7 Fine Fe~O~
Concentrate50.3 56.853.7 53.157.0 63.6 Tail~ 49.7 43.241.0 40.043.0 36.4 Rutile Concentrate11.0 10.141.7 50.152.125 57.5 Tails 89.0 89.94.7 4.247.5 42.9 The data above shows that, in each case, the overall recovery of the desired metal is increased by the practice of the present invention.
38,597-F -11-.
Example 5 -- Hydrocyclone SeParation A one inch hydrocyclone unit having a constant feed slurry pumping device was used. Steady state feed conditions and a uniform discharge fan were established prior to sampling the underflow and overflow discharge.
The feed slurry of hematite ore contained 34.6 weight percent SiO2 and was about 6 weight percent solids.
When used, the alkanol amine was added to the slurry feed box which wa~ highly agitated to insure uniform feed to the cyclone. Samples were sized on standard screens to detect any shift in separation efficiency.
The results obtained are shown in Table V below.
TABLE V
Underflow Overflow Dosage Alkanolamine (kg/met % % - % % ~-ton) Total 75 Total 38 ~ SiO2 Weight _ Weight ~m None~ ___ 86.9 80.5 13.1 60.1 70.3 Diethanolamine 0.45 82.6 81.1 17.463.4 75.4 Diethanolamine 0.90 81.1 81.9 18.964.7 78.7 Monoethanolamine 0.90 83.5 80.9 16.562.7 73.5 ~Not an embodimen ~ of the inventi on.
~u 38,597-F -12-. .
.
Example 6 -- HYdrocYclone SeParation The process described in Example 5 was used with the exception that the ore used was a phosphate ore containing 58.1 weight percent SiO2. The results obtained are shown in Table VI below.
TABLE VI
Underflow ~verflow Dosage Alkanolamine (kg/met % % - % % -ton) Total 75 Total 38 % SiO2 Weight ~m Weight ~m None~ ___ 89.7 90.4 10.3 84.5 60.04 Diethanolamine 0.45 86.3 92.3 13.7 86.0 63.7 Monoethanolamine 0.45 88.4 91.1 11.6 84.9 1 62.3 ~Not an embodimen , of the nvention.
The data in Tables V and VI show that the use of the alkanol amines increases the amount of silica containing fines removed from the two ores teQted. It iq alqo clear that while the weight percent of material included in the coarse underflow decreases slightly, the percentage of that material which iq of the desired larger particle size increases.
Example 7 -- Viscosit~ Effects on Silica Slurries An aqueous silica slurry containing 60 weight percent solidq and 82.4 weight percent leqs than 75 ~m was prepared. The qamples were well mixed and then viscosity was measured uqing a Brookfield RVT vi~cometer with a T-bar and helipath ~tand. The ~ample~ were 38,597-F -13-.
allowed to stand undisturbed for 24 hours after viscosity measurements are taken and then the height of the solid rich lower zone was measured. The data obtained is shown in Table VII below.
TABLE VII
Dosage Viscosity Height of Alkanolamine kg/metric (cps xSolid Zone ton 100) (cm) None ___ 46 8.9 Diethanolamine O. 45 50 11.3 0.90 55 13.7 2.00 62 15.4 .
Monoethanolamine O. 45 49 10.5 Isopropanolamine O. 45 48 10.1 Hexanolamine O. 45 47 9.6 Triethanolamine O. 45 47 9.3 The data in Table VII shows that the alkanol amines of the present invention have a general effect on the viscosity of aqueous silica slurries and on the rate or degree of settling of the silica particles when left 25 undisturbed. The alkanol amine appears to keep the fined silica particles in suspension to a greater degree.
38,597-F - 14-i, - ' ' -- ~ .
.....
methods include the use of screening, wet cyclones, hydroseparators, centrifuges, heavy media devices, desliming vessels, jigs, wet tables, spirals, magnetic separators and electro~tatic separators. The proper use of water is recognized as critical to the efficiency of such methods. A fundamental driving force in most of these operations ls the control of how particles flow, settle or are magnetically or electrically manipulated in an aqueous environment. Factors such as the density (percent solids by weight) of the solid mixture solutions in water; the degree of mechanical agitation of such pulps; the size of particles in the solid mixtures; and the equipment design and size all act and/or are controlled in a complex fashion to optimize the appropriate solid separation in any specific operation. While some universal scientific and engineering concepts can be applied in such separations, the complexity of such operations frequently requires empirical testing and adjustment to effect a suitable separation.
The present invention is a solid/solid separation process wherein an aqueous slurry of solids containing silica or siliceous gangue and one or more desired minerals is mechanically separated, characterized by the addition of an amount of an alkanol amine to the aqueous slurry effective to modify the interaction of the silica or siliceous gangue with the aqueous medium such that separation of the silica or siliceous gangue from the remainder of the solid minerals is enhanced when compared to processes conducted in the absence of the alkanol amine.
38,597-F -2-;
;,, -3- ~
Mechanical separation refers to those methods in which an aqueous slurry of solid particles is separated based on the physical characteristics of the particles. Such physical characteristics include size, conductivity, density, magnetic permeability and electrical conductivity.
Typical means used to separate solid/solid pulps include jigs, wet tables, spirals, heavy media devices, screening, wet cyclones, hydroseparators, centrifuges, desliming vessels, magnetic separators and electrostatic separators. These techniques are well known in the art and are extensively practiced. A
general discussion of these techniques is found in Perry's Chemical Engineers' Handbook, Sixth Edition, edited by Don W. Green, McGraw-Hill Book Company.
The t~pical manner of practicing these method~
of mechanical separation is not modified by the practice of this invention, other than by the addition of the alkanol amine.
Typically, mechanical separation is used to separate particulate solids with sizes ranging from about 100 millimeters (mm) in diameter down to particles of less than 0.001 mm in diameter. Particles of this size range may be obtained in various ways, but are typically obtained by wet grinding. Once ground, the particles are present in an aqueous slurry ranging from 2 to 70 percent by weight solids depending on various factors such a~ the particular method of solid separation used and other related operating condition 38,597-F -3-, , ~ .
`2072i~1~
The alkanol amines of the present invention preferably correspond to the formula Wherein R1, R2 and R3 are individually in each occurrence hydrogen or a C(1-6) hydroxy alkyl moiety.
Preferred alkanol amines are monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, hexanolamine and mixtures thereof. The most preferred alkanolamine is diethanolamine. It will be recognized by those skilled in the art that commercial methods of production of such compound~ as diethanolamine result in a product containing some by-products such as other alkanol amines. Such commercial products are operable in the practice of the present invention. It will also be recognized that the alkanol amines are themselves compounds and do not form a part of a larger molecule.
The amount of such alkanol amines used in the process of this invention is that which is effective to result in increased recovery of the desired solid either through improved grade, improved recovery or a combination thereof. This amount typically ranges from 0.01 to 10 kilogram of alkanol amine per metric ton of dry feed. Preferably, the amount ranges from 0.05 to 1 kg per metric ton and more preferably from 0.1 to 0.5 kg per metric ton.
The alkanol amine is added to the aqueous ; slurry feed prior to the feed being fed to the separation device. It is preferred that, when the ~olid feed is subjected to grinding that the alkanol amine be added to the grinding step.
:,, 38,597-F -4-, .. . .
Example 1 -- Ma~netic SeParation A continuous 12 inch diameter by 7 inch width wet drum magnetic separator (ERIEZ Laboratory Model 500-11-11) is set up to run at twenty-five percent of maximum intensity using 115 volts and 5.2 amp input.
Several batches of feed material were prepared using a mixture of magnetite with a specific gravity of 3.96 and silica with a specific gravity of 2.67. The feed mixture of particles was 15.5 weight percent magnetite.
The feed mixtures were prepared in aqueous slurry form at 20 weight percent solids in a special highly agitated slurry holding tank that provided a uniform feed slurry to the magnetic separator. In one run, no pre-treatment was used and in the second run, the slurry was treated with diethanolamine in an amount equivalent to 0.45 kg per metric ton of dry feed solids. Each run wa~
operated at steady state conditions and samples were collected from the concentrate, overflow and tail for five minutes. The samples were dried, weighed and an iron analy~is done with a D.C. plasma spectrometer to determine that fate of the magnetite. The re~ults obtained are shown in Table I below.
38,597-F -5-TABLE I
_= ~ ~ i A ~ Fr G t I n 1 Or~e ~r lle~ ~ very ~f re Comparison Concentrate 0.328 0.423 0.874 Run ~ Overflow 0.034 0.006 0.001 Tail 0.638 0.031 0.125 DEA Concentrate 0.292 0.482 0.925 Run Overflow 0.035 0.001 0.000 Tail 0.673 0.017 0.075 ~Not an emb ~diment of t~ e invention The data above shows that the addition of diethanolamine results in more iron being recovered in the concentrate and less iron lost in the tailings.
ExamDle 2 A 0.6 x 1.3 m laboratory table separator was used with 0.01 m openings between the rib~ which measured 0.003 by 0.0017 m. The table angle was 10 degrees from hori~ontal with moderate agitation and water washing. The feed material used was 15.5 weight percent magnetite with the remainder silica. The same slurry feeding system was used and all table operating conditions and slurry feed rates were held constant in each run. Two steady state runs were made at 20 weight perçent solids in an aqueous slurry. Sampling of product, middlings and tail were made for seven minutes 3o in each run. All samples were dried, weighed and analyzed for iron using a D.C. plasma spectrometer. The definition of samples with this table is defined by the physical placement of overflow trays. The re3ults obtained are shown in Table II below.
38,597-F _~_ ' : l TABLE II
Grade of Fractlonal Sampling Fractional Fe in Recovery of Fe Point Wt. Split Sample ln Sample i Comparison Product 0.213 0.359 0.493 Run ~ Meddlings 0.276 0.148 0.264 Tail 0.511 0.074 0.244 , DEA Product 0.233 0.378 0.568 Run Meddlings 0.117 0.178 ` 0.134 Tail 0.650 0.071 0.298 ~Not an emb( )diment of t~ e invention The data above shows a significant increase in the amount of iron recovered. The primary effect appears to be in the ~hift of iron from the middlings to the product.
Example 3 Samples of ~pecified ores (300 g each) were ground in an eight inch diameter ball mill using one inch diameter stainlesc steel balls to obtain approximately 50 weight percent less than 37 micrometers in diameter. The mill was rotated at 60 revolutions per minute (RPM) and 600 cm3 of water was added along with any desired chemical to the mill before grinding was initiated. When the target grind size is achieved, the mill contents were transferred to a 10 liter vessel and the contents were diluted with water to make up a total pulp volume of 10 liters. The dilute pulp was mixed for one minutes at 1800 RPM and then 3ettling wa~ allowed to occur for five minutes. Then seven liters of the pulp from the upper zone of the veq~el were decanted. The dry weights of both the decanted ~olid~ and the settled solids were recorded and the weight percent in the 38,597-F -7-.
deslimed fraction was calculated. The higher this deslime weight fraction, the more efficient the desliming or fine particle removal process.
The three ores chosen were an iron ore containing 32 weight percent silica; a copper ore containing 76 weight percent silica and siliceous gangue and a phosphate ore containing 44 weight percent silica and siliceous gangue. The identity and dosage of the alkanol amines used is shown in Table III below.
3o 38,597-F -8-a = a~ cr~ ~ rr~ ~ ~ n _ ~ o ~ s . ......... ..... . . .
~ 0~ ,S" O ~ C~ ~ ~ ~ ~ 'D ~ ~O 'D
o o ~ u~ ~ o _ ~ .
.~ a) ~D ~ ~ O ~ o ,_ ~ ~
CL S ~ CO ~ N CJ` O ~1S~ `D O O O
o co a~ coc~c~ a~ CJ~ a~
'O _ _ __ s a~ ~ CJ~ ~O ~ L~ O ~ ~ N ~) s., s ~ o ~ u~ ~ ~ ~ t--CO N ~ ~I
~ ,_, 0 COcO COCOCOCOCO CO CO CO
'O ~ _ _ _ _ O .5: 0 ~ CC) ~ O ~O`D U'\ ~ ~
~ o ~ N N N N N ~ t~ N N N
o~ ~: _ _ C~
,s., _ _ _ C~ EL1 O oQ. O N O t~i ~1~ ~ CO ~ CO
~ ~ ~ -- --~ ~ a~ ~r ~u~ ~ s ~ o .~ O S., ~r) ~ ~ J D--J 'D 1~ O co 3 s O ~J ~ J ~ _ N .-~J _ _ _ ~ :
0~ I ~ 000 U- ~ O I~
o ' ~' I ' .
207217~
1 o--The data in Table III shows that various alkanol amines are effective in increasing the percentage of very fine particles removed in a desliming process. As in this example, the very fine (high surface area) particle~ present in many finely ground mineral samples are rich in undesired silica and/or siliceous gangue. Their removal is important in subsequent treatment steps involving the addition of chemical reagents such as in flotation.
Example 4 A standard five turn Humphrey spiral was set up with constant feed pulp and feed water capability. Only one concentrate port was used (remainder were sealed off with ~mooth discs) to obtain consistent steady-state condition~. Sufficient wash water was supplied to maintain a rea~onably ~mooth flow pattern over the concentrate port which was located at the bottom of the first spiral turn. Each run described in Table IV below consists of a five-minute sampling period with the feed rate being 3.0 kg of a 20 weight percent solid slurry over the five minute period. Four different ores were used: (1) cassiterite (SnO2) containing 0.65 weight percent tin with 1.2 weight percent larger than 10 mesh and 9.9 weight percent ~maller than 200 mesh; (2) coarse hematite (FeO3) containing 33.1 weight percent iron with 8.6 weight percent being larger than 10 mesh and 2.1 weight percent being smaller than 200 mesh; (3) fine hematite containing 47.4 weight percent iron with 0.0 weight percent being larger than 10 mesh and 28.3 weight percent being smaller than 200 mesh; and (4) coarse rutile (TiO2) containing 8.8 weight percent iron with 11.4 weight percent being larger than 10 mesh and 4.9 38,597-F -10-;, .
.
weight percent being smaller than 200 mesh. In each run, all samples were collected, dried and weighed and metal content determined by a D. C. plasma spectrograph When the diethanolamine was used, the feed slurry was conditioned for one minute in a stirred tank before 5 slurry feed addition to the spiral was initiated. The results obtained are shown in Table IV below.
TABLE IV
Wt % OreGrade of % of Metal Ore RecoveredRecovered Ore Recovered SnO2 No DEA DEANo DEA DEANo DEA D~A
Concentrate34.1 39.61.34 1.3270.3 80.4 Tail 65.9 60.40.29 0.2129.4 19.5 Coarse Fe20~
Concentrate38.0 35.438.1 45.043.7 48.1 Tail 62.0 64.630.1 26.556.4 51.7 Fine Fe~O~
Concentrate50.3 56.853.7 53.157.0 63.6 Tail~ 49.7 43.241.0 40.043.0 36.4 Rutile Concentrate11.0 10.141.7 50.152.125 57.5 Tails 89.0 89.94.7 4.247.5 42.9 The data above shows that, in each case, the overall recovery of the desired metal is increased by the practice of the present invention.
38,597-F -11-.
Example 5 -- Hydrocyclone SeParation A one inch hydrocyclone unit having a constant feed slurry pumping device was used. Steady state feed conditions and a uniform discharge fan were established prior to sampling the underflow and overflow discharge.
The feed slurry of hematite ore contained 34.6 weight percent SiO2 and was about 6 weight percent solids.
When used, the alkanol amine was added to the slurry feed box which wa~ highly agitated to insure uniform feed to the cyclone. Samples were sized on standard screens to detect any shift in separation efficiency.
The results obtained are shown in Table V below.
TABLE V
Underflow Overflow Dosage Alkanolamine (kg/met % % - % % ~-ton) Total 75 Total 38 ~ SiO2 Weight _ Weight ~m None~ ___ 86.9 80.5 13.1 60.1 70.3 Diethanolamine 0.45 82.6 81.1 17.463.4 75.4 Diethanolamine 0.90 81.1 81.9 18.964.7 78.7 Monoethanolamine 0.90 83.5 80.9 16.562.7 73.5 ~Not an embodimen ~ of the inventi on.
~u 38,597-F -12-. .
.
Example 6 -- HYdrocYclone SeParation The process described in Example 5 was used with the exception that the ore used was a phosphate ore containing 58.1 weight percent SiO2. The results obtained are shown in Table VI below.
TABLE VI
Underflow ~verflow Dosage Alkanolamine (kg/met % % - % % -ton) Total 75 Total 38 % SiO2 Weight ~m Weight ~m None~ ___ 89.7 90.4 10.3 84.5 60.04 Diethanolamine 0.45 86.3 92.3 13.7 86.0 63.7 Monoethanolamine 0.45 88.4 91.1 11.6 84.9 1 62.3 ~Not an embodimen , of the nvention.
The data in Tables V and VI show that the use of the alkanol amines increases the amount of silica containing fines removed from the two ores teQted. It iq alqo clear that while the weight percent of material included in the coarse underflow decreases slightly, the percentage of that material which iq of the desired larger particle size increases.
Example 7 -- Viscosit~ Effects on Silica Slurries An aqueous silica slurry containing 60 weight percent solidq and 82.4 weight percent leqs than 75 ~m was prepared. The qamples were well mixed and then viscosity was measured uqing a Brookfield RVT vi~cometer with a T-bar and helipath ~tand. The ~ample~ were 38,597-F -13-.
allowed to stand undisturbed for 24 hours after viscosity measurements are taken and then the height of the solid rich lower zone was measured. The data obtained is shown in Table VII below.
TABLE VII
Dosage Viscosity Height of Alkanolamine kg/metric (cps xSolid Zone ton 100) (cm) None ___ 46 8.9 Diethanolamine O. 45 50 11.3 0.90 55 13.7 2.00 62 15.4 .
Monoethanolamine O. 45 49 10.5 Isopropanolamine O. 45 48 10.1 Hexanolamine O. 45 47 9.6 Triethanolamine O. 45 47 9.3 The data in Table VII shows that the alkanol amines of the present invention have a general effect on the viscosity of aqueous silica slurries and on the rate or degree of settling of the silica particles when left 25 undisturbed. The alkanol amine appears to keep the fined silica particles in suspension to a greater degree.
38,597-F - 14-i, - ' ' -- ~ .
.....
Claims (9)
- THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS
FOLLOWS:
l. A solid/solid separation process wherein an aqueous slurry of solids containing silica or siliceous gangue and one or more desired minerals is mechanically separated, characterized by the addition of an alkanol amine, corresponding to the formula Wherein R1, R2, and R3 are individually in each occurrence hydrogen or a C(1-6) hydroxy alkyl moiety, to the aqueous slurry in an amount effective to modify the interaction of the silica or siliceous gangue with the aqueous medium such that the separation of the silica or siliceous gangue from the remainder of the solid minerals is enhanced. - 2. The process of Claim 1 wherein the alkanol amine is selected from the group consisting of diethanolamine, monoethanolamine and mixtures thereof.
- 3. The process of Claim 1 wherein the solids contained in the aqueous slurry are subjected to a grinding step prior to being mechanically separated.
38,597-F -15- - 4. The process of Claim 3 wherein the alkanol amine is added to the grinding step.
- 5. The process of Claim 4 wherein the alkanol amine is selected from the group consisting of diethanolamine, monoethanolamine and mixtures thereof.
- 6. The process of Claim 1 wherein the solid/solid separation process was wet tables.
- 7. The process of Claim 1 wherein the solid/solid separation process was desliming vessels.
- 8. The process of Claim 1 wherein the solid/solid separation process was hydroseparators.
- 9. The process of Claim 1 wherein the alkanolamine is used in an amount of from 0.01 to 10 kilograms of alkanolamine per metric ton of dry feed.
38,597-F -16-
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US719,903 | 1991-06-24 | ||
| US07/719,903 US5244155A (en) | 1991-06-24 | 1991-06-24 | Solid-solid separations utilizing alkanol amines |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2072170A1 true CA2072170A1 (en) | 1992-12-25 |
Family
ID=24891846
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002072170A Abandoned CA2072170A1 (en) | 1991-06-24 | 1992-06-23 | Solid-solid separations utilizing alkanol amines |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US5244155A (en) |
| EP (1) | EP0520739B1 (en) |
| AU (1) | AU645912B2 (en) |
| CA (1) | CA2072170A1 (en) |
| RU (1) | RU2078614C1 (en) |
| ZA (1) | ZA924538B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19612769A1 (en) * | 1996-03-29 | 1997-10-02 | Basf Ag | Mixtures suitable as carrier material for solid electrolytes or separators for electrochemical cells |
| US6536595B2 (en) | 2001-05-02 | 2003-03-25 | Ge Betz, Inc. | Mineral ore flotation aid |
Family Cites Families (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2014405A (en) * | 1932-10-12 | 1935-09-17 | Weed Floyd | Concentrating iron ores by froth flotation |
| US2014406A (en) * | 1932-10-12 | 1935-09-17 | Weed Floyd | Method of concentrating nonsulphide minerals by froth flotation |
| DE1482397A1 (en) * | 1963-11-22 | 1970-03-12 | Eichborn Dipl Ing Joh Ludw V | Application of adsorptive aids for dry grinding |
| US3443976A (en) * | 1965-10-14 | 1969-05-13 | Grace W R & Co | Mineral grinding aids |
| US3608836A (en) * | 1969-04-11 | 1971-09-28 | Ppg Industries Inc | Process of reclaiming offgrade titanium dioxide |
| US4162045A (en) * | 1976-05-19 | 1979-07-24 | The Dow Chemical Company | Ore grinding process |
| US4162044A (en) * | 1976-05-19 | 1979-07-24 | The Dow Chemical Company | Process for grinding coal or ores in a liquid medium |
| DD128454A1 (en) * | 1976-11-30 | 1977-11-16 | Adolf Kirsten | PREPARATION OF FINE-CORE MATERIALS BY MEANS OF MAGNETIC MELT |
| US4226672A (en) * | 1977-07-01 | 1980-10-07 | Ici Australia Limited | Process of separating asbestos fibers and product thereof |
| US4274599A (en) * | 1977-11-21 | 1981-06-23 | The Dow Chemical Company | Ore grinding process including a grinding aid of an anionic polyelectrolyte |
| SU1135497A1 (en) * | 1983-04-06 | 1985-01-23 | Белорусский Ордена Трудового Красного Знамени Технологический Институт Им.С.М.Кирова | Method of benefication of clay-carbonate sludge from sylvinite ores |
| SU1461514A1 (en) * | 1986-11-18 | 1989-02-28 | Институт минеральных ресурсов | Method of dressing ferrous-containing ores |
| SU1586778A1 (en) * | 1988-06-08 | 1990-08-23 | Научно-Производственное Объединение "Армцветмет" | Method of grinding sands |
| JPH0298367A (en) * | 1988-10-05 | 1990-04-10 | S K K:Kk | Suction type heat remedy device |
| US5131600A (en) * | 1989-02-13 | 1992-07-21 | The Dow Chemical Company | Alkanol amine grinding aids |
| US5057209A (en) * | 1989-04-11 | 1991-10-15 | The Dow Chemical Company | Depression of the flotation of silica or siliceous gangue in mineral flotation |
| CA2014882C (en) * | 1990-04-19 | 1996-02-20 | Richard R. Klimpel | Depression of the flotation of silica or siliceous gangue in mineral flotation |
| US5124028A (en) * | 1990-06-28 | 1992-06-23 | The Dow Chemical Company | Froth flotation of silica or siliceous gangue |
-
1991
- 1991-06-24 US US07/719,903 patent/US5244155A/en not_active Expired - Fee Related
-
1992
- 1992-06-19 ZA ZA924538A patent/ZA924538B/en unknown
- 1992-06-23 AU AU18473/92A patent/AU645912B2/en not_active Ceased
- 1992-06-23 RU SU925052333A patent/RU2078614C1/en active
- 1992-06-23 EP EP92305751A patent/EP0520739B1/en not_active Expired - Lifetime
- 1992-06-23 CA CA002072170A patent/CA2072170A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| EP0520739B1 (en) | 1997-05-07 |
| US5244155A (en) | 1993-09-14 |
| EP0520739A2 (en) | 1992-12-30 |
| ZA924538B (en) | 1993-12-20 |
| AU1847392A (en) | 1993-01-07 |
| RU2078614C1 (en) | 1997-05-10 |
| AU645912B2 (en) | 1994-01-27 |
| EP0520739A3 (en) | 1994-03-30 |
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